As from the 1st of April, the European Patent Office (EPO) acting as International Searching Authority under the Patent Cooperation Treaty (PCT) may contact applicants for informal clarification. Indeed, in case you file an international application on or after this date or have a pending application, you may be contacted by an EPO examiner.According to the EPO, the request for informal clarification can occur in those cases where the description, the claims or the drawings are not in accordance with the requirements and, in particular, where the lack of clarity does not allow a meaningful search. In case applicants do not reply to the examiners they may face the risk of not getting a full international report. Nevertheless, this practice is informal and therefore the EPO notes that no sanction will be applied to the applicants ignoring the request.
The European Patent Office, http://www.epo.org